I don’t get it. Both sides now understand that the final bill will be a compromise between Reid and Boehner. If you’re a Republican, why hand Reid extra leverage in those negotiations by helping him to pass his own plan? The Democrats are going to knock down Boehner’s bill tonight; the GOP should turn around and knock Reid’s down too. That would preserve the Republican talking point that they’ve passed two bills in the House while the Democrats have passed nothing in the Senate and it’ll reduce some of Reid’s clout when he huddles with Boehner and McConnell. Instead, Brown sounds ready to give Reid bipartisan cover. Why? He can placate Massachusetts voters by voting for the final bill instead.

He keeps daring conservatives to primary him and hand that Senate seat back to the Democrats. One step too far this time?

“Sen. Brown tells WBUR parties need to work across the aisle to resolve debt-ceiling impasse; he’d vote for Reid’s plan,” the Boston public radio station posted on its Twitter account…

“Senator Brown will support a bill that contains spending cuts and doesn’t increase taxes and allows us to avoid default,” said Marcie Kinzel, spokeswoman for Brown. “That could be a Republican bill, or a Democrat bill – it doesn’t matter.”

Maine Sen. Olympia Snowe said she couldn’t vote to proceed to the Reid plan, but she said “that’s not meant to say there aren’t issues between the Reid and Boehner plan that couldn’t be worked out.”

There’s no audio of the WBUR interview but Greg Sargent confirmed with the reporter who conducted it that Brown said he’d vote for Reid’s bill. Meanwhile, Bob Corker sounds iffy on short-term debt-ceiling hikes, which may or may not mean that he’d support Reid’s long-term solution instead. If Reid can get those two plus the Snowe/Collins/Murkowski squish caucus plus the GOP retirees who have nothing to lose (Kyl, Coburn, and Hutchison), then he can get to 60 even without Joe Manchin. Which is not to say that he will get there — it’s unfathomable that, after House Democrats held out against Boehner, Senate Republicans wouldn’t repay the kindness to Reid — but there’s your bipartisan nucleus for passage of the final compromise bill this weekend.

Cantor says Boehner has the votes in the House, so today’s suspenseful second attempt at a floor vote … ain’t so suspenseful. But don’t fret: Thanks to Brown, there’ll be drama later tonight in the Senate. And who knows? If things wrap up by early evening, we may yet see details of a compromise package start to leak before the day is through. Exit quotation from Reid: “The only compromise there is, is mine.” Click the image to watch.